Coryndon. l that the calf of Hh. simus " always runs in front of
the cow, while the calf of Hh. bicornis invariably follows its
mother." Both animals of course have two horns, and upon the
varying proportions of the horns a large number of " species " have
"been made in the past. It is stated that the longest horn of the
" White Rhinoceros " known measures 56^- inches; while that of
Pia. 133. — Head of HJiinoceros biconvis.
M. bicornis is shorter, 40 inches being apparently the maximum.
But the animal is smaller.
The possible third African species of Rhinoceros2 has been
provisionally named after Mr. Holinwood, and is based upon two
horns 41 and 42 inches long, which, may be abnormal horns
of JRh. Ificornis ; but they are thinner and have a smaller pedicel.
Extinct HMnocerotidae.. — The existing Bhinoceroses are thus
confined to Africa, to certain parts of the continent of Asia, and
to some of the large Islands lying to the south of that continent.
But formerly the genus, and allied genera, had a -wider range.
As far back as the Miocene we meet with remains of Rhinoceroses
closely allied to existing forms. The more ancient forms have, as
is natural, more ancient characters. Thus in Mh. scTileiermacTteri
of fete Miocene, canines appear to have been present. The
Miocene ^dceratJieriif-m,, primitive in the absence of horns as its
SSooL $00. 1894, p. 329. See also Mr. Selous' paper in Proc. Zool, Soc.
,*'F. I*. Sclater, JPVoc. Zo&l. So&. 1893, p. 514=.